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Eu_sst: 20% probability for large satellite collision

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Re: Eu_sst: 20% probability for large satellite collision

#41

Post by airza »

est31 wrote: post #19
barbazoo wrote: post #17

Earlier quoted context omitted.

> Here's the text without having to execute arbitrary code from twitter Ok, I'll bite, what's this about? What "arbitrary" code is being executed when you visit Twitter?

You're running Javascript. It's sandboxed, which is why I have it enabled by default, but often the javascript in a website is made to spy on you and your behaviour. It's not on your side but on the side of the people who made the website. Personally I'm ok when something like discord breaks as it contains real time updates. But twitter just displays a bunch of text and pictues in a non real time manner. Even video c…

That's not arbitrary code in the security sense though. It's the very narrow range of things which are permitted to run in a javascript sandbox (more or less "things javascript can do in a web browser context, minus the extremely small chance someone is trying to drop a JS 0day on you using this link")

Re: Eu_sst: 20% probability for large satellite collision

#43

Post by eqvinox »

JshWright wrote: post #39
eqvinox wrote: post #32

Earlier quoted context omitted.

Put quite simply - the energy doesn't go into destroying objects. There's only a very small amount going into heating things up from mechanical deformation [and a bit into spinning], but fundamentally, splitting something in a million pieces just means you have a million pieces that have the same total kinetic energy in orbit. However, they also exchange kinetic energy & impulse with each other, meaning you get a mix…

I think of "peripheral" as being "far from the center of my vision". Fortunately, years of Kerbal Space Program means the apo/peri prefixes are pretty solidly ingrained.

Ah crap :/

…well I guess the "center of vision" is the center of the orbit ellipse… ;D

(just trying to salvage the mnemonic aid for myself)

Re: Eu_sst: 20% probability for large satellite collision

#44

Post by _0ffh »

eqvinox wrote: post #32
moring wrote: post #23

Earlier quoted context omitted.

Can somebody give a layman explanation why the debris would stay in the same orbit? I would expect a lot of energy to go into destroying both objects, especially in a head-on collision.

Put quite simply - the energy doesn't go into destroying objects. There's only a very small amount going into heating things up from mechanical deformation [and a bit into spinning], but fundamentally, splitting something in a million pieces just means you have a million pieces that have the same total kinetic energy in orbit. However, they also exchange kinetic energy & impulse with each other, meaning you get a mix…

My mental crutch was always Apogee Software. It's more intuitive that someone calls their company "High Point Software" than "Low Point Software".

Re: Eu_sst: 20% probability for large satellite collision

#45

Post by meowster »

mikewarot wrote: post #38

Tangent: I went to find UTC, and they've redesigned time.gov, it looks great on my desktop. https://time.gov/

It happened about a year ago, and I think one of the developers commented on HN:

https://news.ycombinator.com/item?id=22272966

Re: Eu_sst: 20% probability for large satellite collision

#48

Post by andrepd »

superkuh wrote: post #2

Here's the text without having to execute arbitrary code from twitter. --- Update: according to #EUSST's latest estimates using data from its surveillance radars, the close approach between #space objects SL-8 R/B & OPS 6182 expected by tomorrow will have a miss distance under 10m and a Scaled Probability of Collision over 20%! +updates to follow soon See the below plot for the conjunction plane at Time of Close Appr…

Replace `twitter.com` with `nitter.eu`:

https://nitter.eu/EU_SST/status/1380120766071635968

Re: Eu_sst: 20% probability for large satellite collision

#50

Post by capableweb »

airza wrote: post #41
est31 wrote: post #19

Earlier quoted context omitted.

You're running Javascript. It's sandboxed, which is why I have it enabled by default, but often the javascript in a website is made to spy on you and your behaviour. It's not on your side but on the side of the people who made the website. Personally I'm ok when something like discord breaks as it contains real time updates. But twitter just displays a bunch of text and pictues in a non real time manner. Even video c…

That's not arbitrary code in the security sense though. It's the very narrow range of things which are permitted to run in a javascript sandbox (more or less "things javascript can do in a web browser context, minus the extremely small chance someone is trying to drop a JS 0day on you using this link")

> That's not arbitrary code in the security sense though

True, you're right.

> It's the very narrow range of things which are permitted to run in a javascript sandbox

Well, yes and no. Narrow scope in terms of what other programming languages offer, yes. But in terms of limiting the amount of information that can leak from the user (you and your browser), it's not that narrow. And since est31 is making the privacy-argument, I'm guessing they are referring to that.

Cover Your Track by EFF showcases how much information is actually leaking and what Twitter et al could do with it: https://coveryourtracks.eff.org/

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